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the base of the thighs. Other surface caterpillars are 

 very similar, and their general appearance is suggestive 

 of a somewhat smudgy, dirty grub. The Dart moth 

 has the fore wings of a pale grey ground colour in 

 the male, dark umber in the female, with various 

 markings. The hind wings are pearly white, clouded 

 towards the hinder edge in the female, and with dark 

 rays. The colour of the body (including the abdomen) 

 varies, like the colour of the fore wings, with the sex. 

 It is lighter in the males than in the females. 



The injury caused by these caterpillars is chiefly 

 done to the tuber, which they eat freely. Large holes 

 are bored into the tuber, and, in course of time, these 

 become so large that the insect lives inside them, con- 

 tinuing to increase the size by constantly feeding. In 

 bad attacks the tubers become little more than a shell, 

 and are spoiled for market purposes. Excepting the 

 potato disease, there is nothing which can do so much 

 damage to the crop as these grubs, and we have seen 

 crops where fully one-half have had to be thrown out of 

 market samples on account of them. Potatoes thus 

 attacked are called " whistlers," and when moved make 

 a rustling sound, suggestive of dry leaves in motion. 



For no assigned reason the severity of attacks varies 

 from season to season ; land becoming infested from 

 110 apparent cause, and freed from them in an equally 

 mysterious manner. They feed on almost any green 

 crop, and show great partiality for turnips and similar 

 crops. The worst attack we remember was on late 

 turnips, sown after a crop of tares cut late in the season. 



